IRRITANT GASES.
The chief are chlorine, sulphurous-acid gas, nitrous-acid gas, and
hydrochloric-acid gas. When diluted, they admit of being inhaled; not so
when pure.
_Chlorine._--This gas has a greenish-yellow color, and a powerful
suffocating odor. It is used to fumigate buildings, being a valuable
disinfectant. Chlorine is employed by the calico-printer and paper-maker
for its bleaching properties. The men who work in an atmosphere slightly
impregnated with it suffer from dyspepsia, but are long-lived, and it
has been supposed to be actually beneficial to consumptives. Any attempt
to inspire chlorine in its concentrated state would at once prove fatal
by closing the glottis and causing asphyxia. When diluted it excites
excessive irritation of the air-passages, cough, difficulty of
breathing, and inflammation.
In poisoning by chlorine, the inhalation of a small quantity of
sulphuretted hydrogen appeared to afford relief in a case reported by
Christison, but with that, or any other of the irritant gases, our
treatment must chiefly consist in the instant removal of the sufferer to
pure air. Then the cautious inhalation of ammonia, sulphuric ether, or
the vapor of warm water, will be useful.
_Sulphurous Acid Gas_ is one of the products formed by the combustion of
ordinary coal. It possesses bleaching and antiseptic properties; and is
very irritating when inspired.
_Nitrous Acid Gas_ is a very violent poison when inhaled, producing
inflammation of the lungs, &c. It has proved fatal in several
instances, when given off by nitric acid.
_Hydrochloric Acid Gas_ is irrespirable in its concentrated state, and
when diluted produces great irritation of the lungs and air-passages.
This gas, which is a waste product in the manufacture of washing soda,
is the chief cause of the barrenness which surrounds soda works where it
is allowed to escape, it being extremely destructive to vegetable life.
_Ammonia._--It has been already noticed (p. 48) that the vapor of
ammonia is poisonous, exciting inflammation of the larynx, bronchitis,
and pneumonia. Serious symptoms have sometimes arisen from its
indiscriminate application in cases of syncope, &c.
III.--SPECIFIC IRRITANT POISONS.
By Specific Irritant Poisons we mean those which, taken internally,
produce local inflammation or irritation, these being of course
indicated by certain constitutional symptoms; but over and above these,
which may be the result of ordinary inflammation, there are certain
specific signs of the action of a poison, in most instances peculiar,
and frequently pointing directly to the poison employed. This group is
one of the utmost importance in Toxicology, and includes substances
acting in many different ways, all, however, giving rise to the common
symptoms of gastric irritation.